Add support for include_str

Author: lnicola

crates/ra_hir_expand/src/builtin_macro.rs

@@ -1,4 +1,6 @@
 //! Builtin macro
+use std::ops::Deref;
+
 use crate::{
     db::AstDatabase, name, quote, AstId, CrateId, EagerMacroId, LazyMacroId, MacroCallId,
     MacroDefId, MacroDefKind, TextSize,
@@ -99,6 +101,7 @@ register_builtin! {
     EAGER:
     (concat, Concat) => concat_expand,
     (include, Include) => include_expand,
+    (include_str, IncludeStr) => include_str_expand,
     (env, Env) => env_expand,
     (option_env, OptionEnv) => option_env_expand
 }
@@ -331,6 +334,20 @@ fn include_expand(
     Ok((res, FragmentKind::Items))
 }
 
+fn include_str_expand(
+    db: &dyn AstDatabase,
+    arg_id: EagerMacroId,
+    tt: &tt::Subtree,
+) -> Result<(tt::Subtree, FragmentKind), mbe::ExpandError> {
+    let path = parse_string(tt)?;
+    let file_id =
+        relative_file(db, arg_id.into(), &path).ok_or_else(|| mbe::ExpandError::ConversionError)?;
+    let text = db.file_text(file_id);
+    let text = text.deref();
+
+    Ok((quote!(#text), FragmentKind::Expr))
+}
+
 fn get_env_inner(db: &dyn AstDatabase, arg_id: EagerMacroId, key: &str) -> Option<String> {
     let krate = db.lookup_intern_eager_expansion(arg_id).krate;
     db.crate_graph()[krate].env.get(key)

crates/ra_hir_expand/src/name.rs

@@ -191,6 +191,7 @@ pub mod known {
         stringify,
         concat,
         include,
+        include_str,
         format_args,
         format_args_nl,
         env,